United States. Office of Management and Budget. "Federal Sector Transactions in the National Income and Product Accounts," in United States. Office of Management and Budget. "Fiscal Year 2008," Historical Tables, Budget of the United States Government (February 5, 2007) : 280-293. https://fraser.stlouisfed.org/title/383/item/6434/toc/118970 , accessed on April 19, 2024.